Portable miner hand lamp



PORTABLE MINER HAND ILAMP Filed Ilm-ch 28, 1940 K H'IERoNYMUs 2,305,161.

Patented Dec. 15, 1942 2,305,161 PORTABLE IVIINER HAND LAMP Kurt Hieronymus, Dresden, Germany; vested in the Alien Property Custodian Application March 28, 1940, Serial No. 326,415 In Germany March 5, 1939 3 Claims. (Cle. Z50- 14) To rescue miners after explosions in` mines it is necessary to get as quickly as possible to the -point of accident. Very often it is doubtful, Whether the miners can be rescued and whether it is worth while to endanger the life of the rescuers. Communication by knock-signals is impossible in many cases already for shorter` distances. It has been proposed to mount wireless installations in mines, so that in case miners are cut off from the outer world they could communicate by wireless means. Even portablerwireless installations fail almost always because they are Very hindering for the miner in his work and are therefore put aside and not at disposal at the decisive moment.

This inconvenience is obviated by the ypresent invention, accordingl .to which an apparatus equipped with an electric battery is used for the provision of a wireless installation, so that in the miners lamp such elements are present which are essential for a Wireless installation. An electric miners hand-lamp or similar instruments, which are permanently attached to the endangered persons and are therefore at disposal in case ofv danger, are most suitable for the actual purpose. The bottom part and the top part of the miners lamp can be easily used as dipolar antenna.

As it is only necessary to equip the miners 1am-p with the elements absolutely necessary for wireless installation, the size of the miners lamp is not substantially increased nor the handiness of the lamp impaired.

In order that the invention may be applied not only forfthe manufacturing of miners apparatus or lamps but may be subsequently mounted on miners lamps already in use, the wireless installation is constructed, according to the invention, as an independent element and equipped with connecting means adapted to the means for connecting the upper and lower part of the miners lamp. IfI the connection is effected by screwthreaded rings, 'the independent wireless element, which in this instance is in the shape of a flat capsule, must have screw-threaded rings so that it is merely necessary to insert this capsule between the top part and the bottom part of the miners lamp and to connect the same with these parts by screwing.

The intermediate element may also be in the shape of a flat ring in which the elements for the Wireless installation are accommodated in n an accordingly shaped outer hollow ring. The intermediate element can in this instance even be flatter, but the outer hollow ring must preferably be protected against damage. This is mostly necessary, when the independent intermediate element is made of insulating material. In this instance the'special -advantage of very good insulation and simultaneous use of the top and bottom parts of the miners lamp as dipolar antenna is attained. The contact arrangements may be easily` accommodated in the insulating` capsule.

The antenna problem is thus solved by making the lamp or certain parts of the same act as antenna, so that rod, wireor extensible antennas are not -necessary which could not withstand the rough handling in the mines.

A wireless casing of metal may evidently also be employed, and the insulation may be effectedv by means of rings or discs. The radiation-reduc'- ing capactiy of the antenna is, however, particularly small when the casing is of insulating material, and therefore such insulating casing will preferably be used.

Any ordinary miners lamp can consequently be transformed to distress signal apparatus smply by insertion of an intermediate element.

As the intermediate element is an independent part according to the invention, the Wireless apparatus is considerably simplied and its cost very low for the reason that the casing alone fullls three very material functions, namely thel encasing, insulation of the antenna, and carrying the connecting elements.

The arrangement presents further the advantage of easy exchangeability and accessibility for controlling and attendance of the Wireless apparatus, of the battery and of the standardizing of the same.

Owing to this invention it will be possible to generally introduce wireless distress call implements. The invention is particularly important for the reason that about 10 millions of miners lamps are in use.

An embodiment of the invention is illustrated by way of example in the accompanying drawing, in which Fig. 1 shows in elevation and 'partly in section a miners lamp with a wirelessinstallation,

Fig. 2 shows the lamp in elevation partly in section, the individual elements being shown separately.

The bottom part of the miners lamp holding the battery is designated by I. This bottom part has Screw threads 2 at its upper end. The top part of the miners lamp is designated by 3 andv has internal screw thread 4, a lamp 5, a bell 6, and a protecting cage 1.

In the lamp shown in Fig.- 1 an intermediate element I Il is inserted for the wireless installation and has screw threads 8 and 9 at the top and bottom end.

In the lamp shown in Fig. 2 an independent capsule-like element of insulating material is employed, which consists of a capsule II with external screw thread 81 on the upper laterally projecting portion of the wall and an internal screw thread 91 on the lower projecting portion of the wall.

The wireless installation may be of any suitable type comprising an antenna coil I2, a dwarf valve I3, a transformer I4, an interrupter I5, and an antenna contact I6.

The wires I'I and I8 are embedded in a sleeve I9 so that, when the lamp is closed, they are inaccessible and securely protected against fire damp.

A spring-controlled press button 20, preferably slightly downwards inclined, is provided for actuating the wireless installation.

The wireless transmission of the distress calls from the distress call lamp which every miner carries with him, passes underground the rock, ore or bands of coal or through the ruins of the collapsed gallery according to the laws of the vagabonding currents. Practical experiments have shown, that preferably low frequencies are suitable for the message transmission in the earth, and such from the range of the sound frequency to the high frequency of at the utmost about 300 kilocycles (k. c.). For distances such as happen underground in the usual rescuing actions of buried miners, the damping 4of these waves in the rock and so on still remain Within the. given frame, so that they can pass through the rock.

, The .vagabonding currents are produced in the rock by the capacitive di-pole effect of the lamp,

as shown in Fig. 3. The upper part of the lamp isvwell isolated relative to the lower part of the lamp and charged with the highest possible alternating potential of the corresponding transmitting frequency. The upper part of the lamp is therefore excited as, so to say, stationary antenna.

The vagabonding radio currents are the stronger in the rock, the more static field lines pass from the upper part and from the lower part of the lamp to the rock wall for instance ofthe gallery, and the less static lines extend useless directly between upper part and lower part of the lamp. A great distance between the upper part and lower part of the lamp is therefore advantageous, and according to the invention the casing for the transmitter has to be made from insulating material. The small capacity of the upper part of the lamp favours therefore the spreading of the vagabonding currents and consequently the radiation of the radio signals.

It is immaterial for the invention according to which principle the high transmitting potential of the antenna is produced. The transmitter, when sound frequency is used, consists for instance of a connection shown in Fig. 4. By depressing a switch knob 20 the contacts I5 of the self-interrupter are approached the one to the other so much that this self-interrupter begins to operate and a chopped direct current flows through the primary winding of the transformer I4. The secondary winding of the transformer I4 is used to feed the .further parts of the transmitter in a well known manner.

I claim: Y

l. A portable miners hand-lamp of the type embodying a metallic top part with a lamp and a metallic bottom part with electric battery connecting elements between said top part and bottom part, comprising in combination with the top part of the hand-lamp and the battery, a wireless apparatus including a supporting element inserted between the top and bottom parts and actuated by the battery current, said wireless apparatus being of the type for transmitting signals.

2. A portable miners hand-lamp as specified in claim 1, in which the wireless installation is an'independent part and has connections at the upper and lower ends adapted to engage into the said connecting elements between the top part and lower part of the miners lamp so that the wireless installation can be inserted as an independent intermediate aggregate.

3. A portable miners hand-lamp as specified in claim 1, in which the independent supporting element containing the wireless installation is constructed of insulating material so that the.

metallic top part of the lamp may be used as a dipolar antenna relative to the bottom part of the lamp which contains the battery.

KURT HIERONYMUS. 

